So basically you stripped the laptop down to bare essentials and it was able to boot? Hmmm. Have you tried swapping the RAM modules out? I am still curious if one of the sticks is causing it.
As per the broken copper heatspreader, I suggest you refrain from using the machine until you find a replacement. If it keeps turning off because it is overheating, it will eventually kill your video card. The fan assembly that you pointed out is available on several online stores for like $130.
http://www.google.com/search?q=B1805...ient=firefox-a